Bulk polytetrafluoroethylene, also known as, e.g., PTFE, (CF2)n, and Teflon™, is applied to blade edges to reduced cutting forces and improve shaving performance. One method to apply PTFE to a razor blade is to spray suspended fine particles of Teflon™ from a spray gun onto the blade edges. The blade edges are then sintered to melt the Teflon™ causing it to spread and adhere to the blade edges.
Chemical vapor deposition (CVD) is another method used to prepare PTFE films on surfaces of a structure. In a CVD process Teflon™ is polymerized in a vacuum system starting from a gaseous species. There are a number of techniques used to break the gaseous species down to the reactive species, CF2, necessary to build the PTFE chain. The techniques include radio frequency and microwave plasmas, electron cyclotron resonance, lasers and thermal CVD. Thermal CVD uses a heated wire or an array of heated wires with relatively large spacing between the wires. During the thermal CVD process the gaseous species comes into contact with the heated wires cracking the gaseous species down to the reactive species. The reactive species then polymerizes on the surface of the substrate. The amount of the reactive species will determine the amount of solid polymer deposited on the surface of the substrate. The number of collisions between the gaseous species and the heated wires will determine the deposition rate of the reactive species on the surface of the substrate. The relatively small surface areas of the heated wires limits the deposition rate of the reactive species on the surface of the substrate.
There is a need to improve the deposition rate of the reactive species on the surface of the substrate during the CVD process.
There is a need to increase the surface area of the heated element which comes into contact with the gaseous species during the CVD process.